Federal investigators in America and 16 other countries have shut down what they say is the largest international money laundering scheme that handled $6 billion in criminal cash.

The US Department of Justice says the Liberty Reserve digital money service had about a million users and processed more than 55 million illegal transactions.  DOJ documents say that the seven people involved in running Liberty Reserve set up the digital cash service as a “criminal business venture” designed specifically to “help criminals conduct illegal transactions and launder the proceeds of their crimes.”

Raids took place in the US, Spain, Costa Rica and other countries, leading to the arrests of five of Liberty Reserve's principals, including its founder, 39-year old Arthur Budovsky.

It’s Budovsky’s second brush with the law over this sort of scheme; he was sentenced to five years in prison in 2006 for another money laundering website called Gold Age.  That sentence was reduced to five years probation.

The Ukrainian-born Budovsky then left the United States and set-up shop in Costa Rica where he eventually took citizenship.  Rather than finding a lawless Internet frontier, San Jose prosecutors had their eyes on Budovsky for two years prior to the latest raids.  Authorities reportedly tracked him to Spain where they arrested him.

US Prosecutors will likely seek Budovsky’s extradition.